471 Development of a Rapid Molecular Assay for Point-of-Care Detection of Treponema pallidum for Early Detection of Syphilis

Abstract Introduction/Objective In 2023, syphilis cases in the U.S. surged to over 209,000, the highest case total since 1950. Current diagnosis of syphilis is limited to clinical recognition and serological testing, which is limited by a lack of sensitivity early in the disease. To improve early detection of primary syphilis, a real-time polymerase chain reaction (PCR) test was developed to directly detect Treponema pallidum (causative agent of syphilis) from relevant clinical samples. Methods/Case Report The test targets two conserved regions within the T. pallidum genome, and also includes an internal control. Reaction conditions were optimized to permit room temperature storage and compatibility with extraction-free and pipette-free direct detection using the Collect-to-Test (C2T)® cartridge and the point-of-care-compatible T-COR 8® instrument. Results The real-time PCR test demonstrated a time-to-detection of under 45 minutes. The test was verified for specificity against 21 non-T. pallidum organisms, and found to have a limit of detection of 1.0 to 5.0 x103 treponemes/mL. Stability testing showed a shelf-life of up to one year at room temperature. Conclusion Initial verification of the T. pallidum test demonstrated 100% specificity and acceptable limit of detection. This test could significantly improve access to early and rapid syphilis diagnosis at the point of care.